Variation in black carbon concentration and aerosol optical properties in Beijing : Role of emission control and meteorological transport variability

Copyright © 2020 Elsevier Ltd. All rights reserved..

Black carbon (BC), which is a by-product with incomplete combustion of carbonaceous materials, can be used as an indicator of combustion emissions and is an important climate forcer. In this study, a spatial-temporal synthesis of BC aerosols and the affecting factors was conducted in urban Beijing. As observed, BC showed a spatial pattern with high concentration in south and low in north. BC concentration evidently decreased by approximately 61% between 2005 and 2017. From 2015 to 2017, the mass ratio of BC/PM2.5 dropped by 28%, which suggested a more efficient effect of control measures to BC than PM2.5. The BC/CO ratio dropped by 22%, which indicated the decreasing emission from fossil fuel sources. With regard to BC loading, the spectral dependence of absorption aerosol exhibited significant seasonal variations. High absorption Ångström exponent (α) was observed during heating season, which reflected the increasing contribution of brown carbon (BrC) to light absorption. Backward trajectory analysis showed that the levels of BC and PM2.5 were high in Cluster-South and Cluster-West. BrC absorption was high in Cluster-West, Cluster-Northwest and Cluster-Northeast, due to the biomass and coal burning for domestic heating and aging processes on a regional scale. The effects of emission control and transport variability on pollutant variation were estimated on the basis of the cluster analysis. Results indicated that the effect of emission reduction was the major reason for the decrease of BC from 2015 to 2017, which resulted in a 34% reduction of BC concentration. Meanwhile, transport variability caused a 15% reduction.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:254

Enthalten in:

Chemosphere - 254(2020) vom: 20. Sept., Seite 126849

Sprache:

Englisch

Beteiligte Personen:

Xia, Yunjie [VerfasserIn]
Wu, Yunfei [VerfasserIn]
Huang, Ru-Jin [VerfasserIn]
Xia, Xiangao [VerfasserIn]
Tang, Jie [VerfasserIn]
Wang, Mian [VerfasserIn]
Li, Jiwei [VerfasserIn]
Wang, Chaoying [VerfasserIn]
Zhou, Chang [VerfasserIn]
Zhang, Renjian [VerfasserIn]

Links:

Volltext

Themen:

Aerosols
Air Pollutants
Beijing
Black carbon
Emission control
Fossil Fuels
Journal Article
Soot
Transport variability
Vehicle Emissions

Anmerkungen:

Date Completed 03.11.2020

Date Revised 03.11.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.chemosphere.2020.126849

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM315285397